#!/usr/bin/python

import ctypes
import ctypes.util

api = ctypes.CDLL(ctypes.util.find_library("gfapi"))
api.glfs_get_volfile.argtypes = [ctypes.c_void_p,
                                 ctypes.c_void_p,
                                 ctypes.c_ulong]
api.glfs_get_volfile.restype = ctypes.c_long;

def get_volfile (host, volume):
	# This is set to a large value to exercise the "buffer not big enough"
	# path.  More realistically, you'd just start with a huge buffer.
	BUF_LEN = 0
	fs = api.glfs_new(volume)
	#api.glfs_set_logging(fs,"/dev/stderr",7)
	api.glfs_set_volfile_server(fs,"tcp",host,24007)
	api.glfs_init(fs)
	vbuf = ctypes.create_string_buffer(BUF_LEN)
	vlen = api.glfs_get_volfile(fs,vbuf,BUF_LEN)
	if vlen < 0:
		vlen = BUF_LEN - vlen
		vbuf = ctypes.create_string_buffer(vlen)
		vlen = api.glfs_get_volfile(fs,vbuf,vlen)
	api.glfs_fini(fs)
	if vlen <= 0:
		return vlen
	return vbuf.value[:vlen]

if __name__ == "__main__":
	import sys

	try:
		res = apply(get_volfile,sys.argv[1:3])
	except:
		print "fetching volfile failed (volume not started?)"

	try:
		for line in res.split('\n'):
			print line
	except:
		print "bad return value %s" % res
